(a) Field of the Invention
The present invention relates to a liquid crystal display.
(b) Description of the Related Art
A liquid crystal display (LCD) is one of the most widely used flat panel displays. An LCD includes two panels provided with field-generating electrodes such as pixel electrodes and a common electrode and a liquid crystal (LC) layer interposed therebetween. The LCD displays images by applying voltages to the field-generating electrodes to generate an electric field in the LC layer, which determines orientations of LC molecules in the LC layer to adjust polarization of incident light.
Among the LCDs, a vertical alignment (VA) mode LCD, which aligns LC molecules such that the long axes of the LC molecules are perpendicular to the panels in absence of electric field, is spotlighted because of its high contrast ratio and wide reference viewing angle that is defined as a viewing angle making the contrast ratio equal to 1:10 or as a limit angle for the inversion in luminance between the grays.
The wide viewing angle of the VA mode LCD can be realized by cutouts in the field-generating electrodes and protrusions on the field-generating electrodes. Since the cutouts and the protrusions can determine the tilt directions of the LC molecules, the tilt directions can be distributed into several directions by using the cutouts and the protrusions such that the reference viewing angle is widened.
However, the cutouts and the protrusions may yield spots or afterimages and the spots generated by scrubbing the LCD are remained. It is because the tilt directions of the liquid crystal molecules near the cutouts and the protrusions are determined by push of the liquid crystal molecules on the field-generating electrodes or by collision with them and thus the alignment of the liquid crystal molecules is unstable and irregular.